Carotid artery pseudoaneurysm

Pseudoaneurysm-Jan-2013.jpg

Image 1

Clinical History: 
Trauma 

Diagnosis:
Carotid artery pseudoaneurysm

MR Technique: 
The exam was obtained at 3 T on a Siemens Tim Trio MR system. Contrast enhanced MRA was performed of the vessels of the neck, using a dose of 20 ml of a macrocyclic gadolinium chelate. A 3D FLASH GRE coronal slab was acquired during suspended respiration with TR/TE/flip angle of 3/1.14/15°. The scan time was 20 sec, with voxel dimensions of .8x.8.x8 mm3. A targeted MIP and a single slice from the source images are presented.

Imaging Findings:
The targeted MIP depicts the internal carotid and vertebral arteries from just proximal to the carotid bifurcation to the horizontal portion of the internal carotid arteries at the skull base. A focal increase in the diameter of the distal left internal carotid artery proximal to the skull base is noted (arrow), with a subsequent short segment decrease in diameter of the vessel. The focal dilatation of the vessel is consistent with a pseudoaneurysm. Dissection of the vessel is often associated, and in this instance may involve the internal carotid artery distal to the pseudoaneurysm. A common etiology is trauma, as in this instance.